Related Experiment Video
Updated: Jun 12, 2026

Simple and Robust in vivo and in vitro Approach for Studying Virus Assembly
Published on: March 1, 2012
Assembly of viruses and the pseudo-law of mass action
Alexander Yu Morozov1, Robijn F Bruinsma, Joseph Rudnick
1Department of Physics and Astronomy, University of California, Los Angeles, Los Angeles, California 90024, USA.
Abstract:
The self-assembly of the protein shell ("capsid") of a virus appears to obey the law of mass action (LMA) despite the fact that viral assembly is a nonequilibrium process. In this paper we examine a model for capsid assembly, the "assembly line model," that can be analyzed analytically. We show that, in this model, efficient viral assembly from a supersaturated solution is characterized by a shock front propagating in the assembly configuration space from small to large aggregate sizes. If this shock front can reach the size of assembled capsids, then capsid assembly follows either the LMA or a "pseudo" LMA that describes partitioning of capsid proteins between assembled capsids and a metastable, supersaturated solution of free proteins that decays logarithmically slowly. We show that the applicability of the LMA and the pseudo-LMA is governed by two dimensionless parameters: the dimensionless nucleation rate and the dimensionless line energy of incomplete capsids.
Related Concept Videos
Protein Complex Assembly
Many viruses self-assemble into a fully functional unit using the infected host cell to...
Viral Structure
What are Viruses?
Intracellular Movement of Viruses and Bacteria
Introduction to Virus
Size and Structure of Viral Genomes

